Some limitations of the present scientific approach are imposed, as it were, from the ‘outside'. They are a result of materialist beliefs not science itself.
Determinism - it is fair to say that determinism is not something that only materialists adhere to. There is a long history of this belief that includes thinkers from very different perspectives. Materialism has only defined determinism in terms of the natural laws. This not only precludes the possibility of purposeful causes, but also of choice and of creativity. Ironically, modern science itself has come to the conclusion that determinism does not fully reflect reality, and yet many, especially human science disciplines, are reluctant to give it up (most psychology text-books, for example, still recognise nature and nurture as the only factors that affect human behaviour).
Reductionism - one of the most stubborn beliefs of modern science is that complex phenomena can always be reduced to simpler, more fundamental ones and the laws that govern them. Mind can be reduced to biology, biology to chemistry, chemistry to physics. This is the essence of reductionism, adopted in the 19th century. However, this belief appears to be a dead-end even on the most basic level. It is already recognised that, for example, ‘the macroscopic behaviour of a large ensemble of particles cannot be deduced from the properties of the individual particles themselves' (Silver, 1998, p.19). Many eminent scientists are ready to admit the improbability of reductionism.
Insisting on material evidence - a position that would always insist on material evidence, and automatically dismiss an argument that is not based on observable data is somewhat naïve. Even hardcore science inevitably operates with phenomena or principles for which material evidence does not exist (e.g. time or causality) or is based on stipulations that cannot be empirically verified (such as the ones linked to the theory of relativity). Also, many scientific concepts (gravitation being one example) cannot be known directly but only through their effects.
The inertia of science has been criticised by a number of scholars (Kuhn, Feyerabend and Lakatos being probably the best known). It transpires in a rigid, absolutistic demand to adhere to certain views and self-imposed methods and criteria. Physicist Max Planck allegedly said that a new scientific truth does not triumph by convincing its opponents, but rather because its opponents die, and a new generation grows up that is familiar with it. This stifles rather than advances human knowledge. As Chalmers points out, ‘we cannot legitimately defend or reject items of knowledge because they do or do not conform to some ready-made criterion of scientificity' (1980, p.169). The best scientists have always been on the front lines, prepared to sacrifice their pre-assumptions for the sake of better understanding. However, there is another, inevitably larger group of scientists that prefer to maintain the status quo. Science writer Horgan comments that ‘the scientific culture was once much smaller and therefore more susceptible to rapid change. Now it has become a vast intellectual, social, and political bureaucracy, with inertia to match' (1995, p.137). Both of these groups, progressive and conservative, may be necessary, the former to prevent the solidification of science, and the latter to prevent chaos. The problem is that the conservative stream often supports and perpetuates particular ideological views in order to maintain a special status and social power. The suspicion is that some scientists are more interested in advancing their careers than knowledge. Chalmers claims that ‘[ideology of science] involves the use of the dubious concept of science and the equally dubious concept of truth that is often associated with it, usually in the defence of conservative positions' (1980, p.169).
Bias - those phenomena to which the established scientific method can be applied are studied in greater and greater detail, often without any reference to a larger picture; whereas those to which it cannot be are ignored or are declared illusionary. The Oxford Companion to the Mind, for example, has entries such as ‘Frankenstein' but not ‘will'. The consequence of such an attitude is a distorted and impoverished picture of reality. Even if some phenomena or events cannot be explained, they need to be taken into account and acknowledged:
Objectivism has totally falsified our conception of truth, by exalting what we can know and prove, while covering up with ambiguous utterances all that we know and cannot prove, even though the latter knowledge underlies, and must ultimately set its seal to, all that we can prove. (Polanyi, 1958, p.286)
Limitations of science as a social practice
Besides the above ideological limitations there are other self-imposed limitations to present day science that are the result of the social milieu within which it operates.
Specialisation is such an instance. The best specialisation can provide is a fragmented picture on reality, which leaves out the possibility of an overall, synthetic view. This can lead to ‘not seeing the wood for the trees', and can have highly undesirable consequences. James Burke, a scientist himself, concludes that ‘the reductionist approach, forcing people to be specialists, has got us into the mess we are in' (The Sunday Times, 1st of January 1995). The one who looks through a microscope all the time may not notice an elephant standing next to shim. Historian Zeldin proclaims:
...around the beginning of the eighteenth century... the ideal of encyclopaedic knowledge was replaced by specialisation. Withdrawal into a fortress of limited knowledge meant one could defend oneself on one's home ground; it gave one self-confidence of a limited kind... Now that the silences produced by specialisation have become deafening, and now that information fills the air as never before, it is possible to reconsider the choice, to ask whether many people might not be better off if they began looking again for the road which leads beyond specialisation, if they tried seeing the universe as a whole. (1994, p.197)
The insistence on observable, public and repeatable is still prevailing, although there are certain phenomena (in cosmology and the realm of sub-atomic particles, as much as in studying life and mind) that cannot satisfy these requirements. Any attempts to fit them within these criteria severely impoverish their understanding. The very existence of atoms was derided as metaphysical nonsense until barely a century ago. Leading scientists argued that it made no sense to talk of entities that could never be observed, which drove one of the most talented scientists at that time, Boltzmann, to suicide. His struggles against the scientific orthodoxy illustrate the dangers of allowing such a dogmatism to seep into the quest for knowledge, especially in the fields of human and social science (the mind is neither observable, nor public, nor repeatable).
Authoritarianism - to secure their special status, priests used to perpetuate a belief that their vocation made them somehow closer to God, so the best way for ordinary people to relate and be informed about spiritual matters was through them. Scientists nowadays acquire a similar aura of authority. The impression is that they are experts above others (fostered not necessarily by scientists themselves, of which some, in all fairness, are trying to break out of such an image). It surfaces in frequently heard statements in the media such as ‘scientists claim that...', without saying who these scientists are and what these claims are based on. This makes science not only vulnerable to manipulation, but also alienates it from ordinary people.
Scientific detachment was introduced to ensure a higher level of objectivity and is often justified (e.g. to enable independent verification). However, it is sometimes taken so far that it becomes an obstacle and, in fact, leads to bias through the back door.
The above ideological and historical limitations are contingent, and should not be taken as detrimental. After all, they can be overcome in the future. However, there are some limitations of science that can never be surpassed, which is why the scientific approach cannot be sufficient on its own and needs to be combined with other approaches.
Dealing with complexity - scientific method is essentially analytic, which enables the simplification and generalisation of some phenomena. Yet, reality is complex, and if that complexity is disregarded, some important qualities can be missed. One of the world's most distinguished quantum physicists and a philosopher, Werner Heisenberg, warned: ‘...the scientific concepts are idealizations... But through this process of idealization and precise definition immediate connection with reality is lost' (1958, p.200). More heuristic methods are better suited to deal with complex systems. Human beings could not operate in the world if they only relied on science and excluded the common sense that is capable of intuitively grasping this complexity. Psychologists, for example, are not yet nearly able to provide the profound insights about the human psyche that can be found in the works of narrative writers such as Shakespeare, Dickens or Tolstoy.
Incompleteness - there are certain phenomena or questions that are beyond the reach of science. For instance, one of the dogmas of the present scientific ideology is that all the processes in nature are governed by physical laws. However, science seems at loss to explain where these laws come from. It is not only a question of why there is this set of laws rather than any other, but more fundamentally, why there are laws at all, why the universe is orderly, rather than chaotic and disorderly. Physicist Paul Davies speculates that attaining full knowledge through science is unlikely, given the limits imposed by quantum indeterminacy, Gödel's theorem, chaos theory and the like. Mystical experience might provide the only avenue to absolute truth, he concludes (in Horgan, 1996, p.261).
A lack of criteria for interpreting facts - Henri Poincaré, one of the greatest mathematicians and physicists in the 19th century, wrote: ‘Just as houses are made of stones, so is science made of facts; but a pile of stones is not a house and a collection of facts is not necessarily science'. What sort of structure is created depends on the way scientists play with or interpret facts. Interpretations are important. Human understanding would be very limited if it was based only on descriptive statements. The laws do not have much explanatory power; they leave many questions unanswered. However, interpretations are not obvious, they are extrapolations that necessarily involve mental operations, not solely based on observations. So, many observable facts can give rise to a number of different interpretations, of which some may not be accurate even if the facts behind them are. A different set of criteria is needed for interpretations than for observations, but scientific method does not provide them. This is why it is easy to highjack scientific findings and present one's interpretations as scientific truths.
To conclude, the scientific approach is no doubt useful for examining natural phenomena, but it is not sufficient to explain reality as a whole. At its best, it can offer an incomplete account of reality. This is not the fault of scientists. After all, few of them have ever promised to provide a full and coherent picture of the world. However, a more comprehensive understanding requires a more comprehensive approach. A professor of Computer Science and Engineering, Joseph Weizenbaum summarises this point in the following statement:
... some people have the same type of very deep faith in modern science that others do in their respective religions. This faith in science, grounded in its own dogma, leads to defence of scientific theories far beyond the time any disconfirming evidence is unearthed. Moreover, disconfirming evidence is generally not incorporated into the body of science in an open-minded way but by an elaboration of the already existing edifice (as, for example, by adding epicycles) and generally in a way in which the resulting structure of science and its procedures excludes the possibility of putting the enterprise itself in jeopardy. In other worlds, modern science has made itself immune to falsification in any terms the true believer will admit into argument. Perhaps modern science's most devastating effect is that it leads its believers to think it to be the only legitimate source of knowledge about the world... This is as mistaken a belief as the belief that one cannot gain legitimate knowledge from anything other than religion. Both are equally false. (in Singh, 1987, p. 281
- . Laszlo paraphrases the renowned physicist Stephen Hawking: ‘Although the goal of physics is a complete understanding of everything around us, including our own existence, physics has not succeeded in reducing chemistry and biology to the status of solved problems, while the possibility of creating a set of equations through which it could account for human behaviour remains entirely remote' (1993, p.48).
- . Neuroscientist Pribram writes: ‘...we think of the force of gravity as a thing. Actually, of course, all we have are the observations of actions at a distance... this means that we are inferring gravity from our observations: gravity is not an observable; as in the case of field concepts, gravity is inferred' (Laszlo, 1993, p.12).
- . It has been observed that ‘it is no coincidence that those who feel most certain of their grip on scientific method have rarely worked on the frontiers of science themselves' (Collins and Pinch, 1993, p.143).
- . Quantum indeterminacy is the apparent necessary incompleteness in the description of a physical system; Gödel's theorem demonstrates that there are always undecidable elements within any formal system; and chaos theory sets the limit to the ability to predict future states from initial conditions.
- . ‘More recent research (Pickering, Galison, Rudwick, and others) has added that scientific facts are constituted by debate and compromise, that they harden with the distance from their origin, that they are manufactured rather than read off nature, and that the activities that produce and/or identify them form complex and, with respect to theory, relatively self-contained cultures' (in Honderich, 1995, p.808).